We paint render and masonry in Cogenhoe, the village on the limestone slope 4.6 miles east of Northampton town centre. Dean will tell you honestly when a wall should stay unpainted, and when it does need a coating he picks one that suits what the wall is made of.
Most of Cogenhoe’s walls were never meant for paint
It is worth starting with what we would not coat. The historic core along Church Street and upper Mill Lane is built of local limestone laid as coursed rubble, with ironstone banding, quoins and mullions on the bigger houses. The Victorian houses lower down Church Street and on Station Road are red brick in English bond, some of it from the brickworks that once stood by the railway, with limestone dressings round the windows. Both look as intended when left bare, and both rely on being able to dry out through the face.
Acrylic masonry paint forms a fairly tight film. On solid stone or soft old brick it can hold moisture in the wall, which then pushes the paint off or damages the surface behind it. The village’s conservation appraisal also asks for limestone boundary walls, with their ironstone or tile copings, to be kept. If you are thinking of painting a stone or brick front to freshen it up, Dean will usually suggest cleaning and repairing it, and spending the budget on the joinery.
The half-stone, half-render cottage
One building type here needs particular care. On Church Street, between Manor Cottage and the Manor House, an early 20th century Arts and Crafts cottage is built half in limestone and half in render. Wherever render meets stone like this, the coating on the render has to match the stone’s ability to breathe. A dense finish on the rendered panel can drive damp sideways into the stone next to it, and leaves a hard line where the two materials age at different rates.
For walls of this kind we look at limewash or a mineral silicate paint. Limewash builds up in thin coats and wears back gently; silicate paint bonds chemically with a mineral surface and stays vapour-open. Either way, the stone around the panel is masked off and kept clean, as are the ironstone quoins where they meet it.
Rendered walls on the newer estates
The 20th century estates west of the conservation area, along Station Road and York Avenue, are where most straightforward render painting in the village happens. Where these houses have rendered walls or panels, a good-quality exterior masonry system is normally the right choice. The work is in the preparation: washing off dirt, treating any algae, raking out and filling cracks, and stabilising chalky old paint so the new coats bond.
Exposure plays a part. The village sits high above the Nene with an open outlook north, and walls facing north and west take wind-driven rain. Render on those sides tends to show green staining and failed patches first, and we would expect to spend more time preparing them than the sheltered faces. Our guide to painting render and roughcast explains the stages in more detail.
Already-painted stone: taking stock first
- We check whether the existing coating is limewash, a mineral paint or a modern film, because that decides what can go over it.
- Where a plastic-type paint is flaking off stone, we discuss whether removal is realistic or whether a compatible recoat is the practical route.
- Modern cement pointing, which the conservation appraisal lists as a threat, can hide damp problems; we will point this out rather than paint over it.
- On listed buildings, any change to an external wall finish should be agreed with West Northamptonshire Council first.
The general method we follow is set out on our render and masonry painting page, and the full list of services we cover in the village is on our Cogenhoe page.
Last updated by Dean, DH Painter & Decorator.
